Siemens 7ML19985AB01 instruction manual = crest width = C = crest height = Cp = crest length

BS-3680 FINITE CREST WEIR, P3 = 5
‘U’ parameters required *			‘U’ parameters calculated **
U0	= crest width	b	U3	= C
U1	= crest height	p	U4	= Cp
U2	= crest length	L

*obtain from manufacturer’s specifications.

**calculated by OCM-3. May be viewed by accessing ‘U’ parameter.

Reference

ABSOLUTE CALCULATION, P4 = 0¤

For flows that can be calculated by the equation:

q = (2/3)1.5 x g0.5 x C x Cp x b x h1.5

where :	q = flow rate	C = a function of h and L
	g = gravitational acceleration
	b = crest width	Cp = a correction factor as a function
	h = head	of h and p applied to C
RATIOMETRIC CALCULATION, P4 = 1¤
For flows that can be calculated by the equation:
q = qcal x C/Ccal x Cp/Cpcal x (h/hcal)1.5
where :	q = flow rate
	qcal = flow rate at maximum head
	h = head

hcal = maximum head

C = discharge coefficient for head

Ccal = discharge coefficient for maximum head

Cp = correction factor for C

Cpcal = correction factor for Ccal

¤Refer to Operation \ Flow Calculation.

7ML19985AB01 OCM III 66